This invention relates to a system of sealing wedge-type gun breech mechanisms.
A former proposal of the claimant (P No. 24 35 520) related to a wedge-type breech mechanism using a sealing ring which is pre-loaded by a gear system, designed for weapons firing caseless ammunition. Both, the sealing ring and the gear system are comprised in a recess provided in the wedge. The sealing ring axially slides into contact with the plane surface of the barrel; this feature is provided by a clamping stud supported by the wedge and an intermediate ring engaged with the clamping stud by a worm. Both, the clamping stud and the intermediate ring are provided with vent holes.
Prior to opening the wedge, load is relieved from the sealing ring by sliding back the intermediate ring. Thus, the sealing ring returns from the plane surface of the barrel, when the wedge extends. This proposal ensures a gasproof sealing of the breech with weapons generating gas pressures up to 4,500 bars. With extremely high gas pressures involved -- up to 8,000 bars -- however, the strength of the lateral walls of the wedge comprising the sealing system is affected to such extent that service life can no longer be guaranteed. The reason is that the wedge is provided with a relatively deep longitudinal recess which is necessary to house the sealing ring and the gear system, thus reducing the bending strength of the lateral walls of the wedge which could be broken.